Control for gunfire



Dec. 3, 1929. C. c. MERTz CONTROL FOR GUN FIRE 2 Sheets-Sheet 1 Filed March 9, 1928 attozmq.

Dec. 3, 1929. c. c. MERTZ 1,737,937

- CONTROL FOR GUN FIRE Filed Maren 9, 192e 2 sheets-sheet 2 6/ Q /zz/ .QZ f "i/ f /5/ /7/ /g ///n J/-X I! 56 j 33 @www amig 36 i i :Jn/vanto@ In z8 6/ I @www Patented Dec. 3, 1929 CHARLES C. MERTZ, OF BALTIMORE, MARYLAND, ASSIGNOR OF ONE-HALF TO ALBERT W. GILL, OF BALTIMORE, MARYLAND CONTROL FOB GUNFIRE Application led March 9, 1928.

This invention relates to an improvement in ordnance and is directed particularly to an improvement in automatic rapid fire arms.

One of the objects of the invention is the provision of means for regulating the rapidity of fire from a machine gun. Another object is the provision of an attachment for rapid lire guns that may be readily adjusted to change the speed of fire or to be entirely dispensed with as occasion may require.

With these and other objects in view, the invention resides in the novel arrangement and combination of parts hereinafter described and particularly pointed out in the appended claims, it being understood that minor changes may be made in the structure, within the scope of what is claimed, Without departing from the spirit of the invention, or sacrificing any of the advantages thereof.

In the drawing:

Figure 1 is a view in side elevation of a portion of the breech of a machine gun, the present invention being attached thereto.

Figure 2 is a plan sectional view taken on the line 2-2 of Figure 1.

Figure 3 is a transverse sectional view the cutting plane being taken on line 3-3 of Figure 1.

Figure 4 is a detail perspective View of a bolt adapted for use with the present invention.

Figure 5 is a view similar to Figure 3 de- 1 picting a modified form of the device.

Figure 6 is a sectional view taken on the line 6 6 of Figure 5.

Figure 7 is a sectional view taken on the line 7 7 of Figure 5.

Figure 8 is a fragmentary sectional view of the cutting plane designated by line 8-8 of Figure 5.

In machine gun tire it has been found that due to vibration of the piece, the stream of bullets describe an ellipse on the target the longer aXis of the ellipse being in a vertical plane. Machine gunners are therefore instructed to fire their weapon in bursts of a limited number of shots, about ten being the required number, and then to bump the gun.` This instruction when properly carried out, produces a target having a series of Serial No. 260,528.

eliptically shaped line of bullet marks, the sides of each ellipse being spaced upon the other, so that the field is practically covered by gun fire.

In practical operation the regulation machine gun fires at such a rapid rate that the gunner invariably fires more shots than the requisite number, resulting in a waste of ammunition.

It is the function of the present Ainvention to reduce thc rapidity of fire and thus enable the `gunner to more accurately do his work.

Referring to the drawings the numeral 1 designates the frame of a machine gun of well known make. T he bolt 2 reciprocates within the frame in a well known manner.

Hingedly connected to the frame intermediate the ends thereof is a housing 3, the hinges being designated by the numeral 4. The housing supports a shaft 5, fixed against rotation by a pin 6 which also serves to secure the shaft to the housing.

A ball governor 7 is mounted for rotation on the shaft 5, the upper disk 8 thereof have ing a ratchet face 9. |The lower disk 10 of the governor is mounted for rotation on a sleeve 11, the sleeve having a stop and brake collar 12 with which the disk 10 may engage. The sleeve 11 is threaded on the shaft 5 and is provided with a knurled linger-piece 13 for adjustment of the brake collar.

A collar 14 is secured to the shaft 5 by means of a pin 15 and supports the governor at its upper end.

Loosely mounted on shaft 5 is a gear wheel 16, the under side of which is provided with a ratchet face 17 for engagement with the ratchet face 9. A spring 18 surrounds the shaft 5 and is interposed between the top of the casing and the gear, 16.

In attaching the .device to the gun frame an opening 19 is made in the frame through which a portion of the gear 16 projects. The breech bolt Q. is also adapted for use of the device by forming a groove 20 in the block which provides clearance for the teeth of the gear projecting within the frame and a gear rack 21 formed on the block for engagement with the gear wheel.

A spring snap latch 22 retains the device in operative position.

' governor is dispensed ,with and a governor including-.an inclined plane is substituted. A sleeve 24 is formed as apart ofthe ratchet disk 8 and has a spiral groovey 25V formed ggftherein. A frame-26. comprising upper and lower heads 27 and 28 connected by bars 29 ism'ountedfor longitudinalmovement in the plane of the sha-ft. The head 27 isprovided with threads to engage the spiral 25. f

A sleeve30isthreadedeXteriorly to engage afthreadedopening in the case 3 and has a knurled. head 31 at one end for rotating the sleeve andaY collarf32'fixed thereto at'the other end. Interposed between the collar 32 and the head 28 isa compression spring 33.

The shaft is fixed to the casing 3 ashereinbefore described., To prevent rotation of the frame 2G so that the-f parts 25 and 2T will be effective-in compressing-the spring 33, #a collar 34 is fixed to the shaft, thecollar has arms 35 which extend through slots 36 formed in the bars 29.- vIn this ymanner longitudinal. movementuofzthe frame 26 is duced to compress the spring` 33, thereby to -`'retardmovement of the. gear 16.

It ,Wil-l be observed that through manipu,

lation ofthe sleeve to increase orfdiminish tensionv inthe spring 33 that the bolt 2 will bei retarded to1 a greater or less amount defzgpendent onthe'tension in the spring.`

It will also be noted that byv releasing lthe latch. 22 the attachment may be moved to an inoperative position and the gun` may then be fired in the ordinary way. i

What is'claimed is: v c.

1a. In-a frearmhaving a reciprocatory bolt',` afly ball governor and meansfor connecting the` governor and the bolt to retard reciprocation of the-bolt.

2. In a device of the class described,`the combination with a gun having a reciprocating bolt,of a fly ball governona; gear for actu- Y ating the governor and a rack'carried by the bolt for engagement with the gear to retard movement of the bolt.

3. Ina device of the class described" a housing, a shaft mounted in the housing, a governor rotatable on the' shaft, aA gear projecting from the housing andr adapted to be rotated" from outside the housing, a flexible connecprol tion between they gear and the governor to permit retroactive movement of the gear and means for regulating speed of rotation of theV governor.

4. In a device of the class described, a gun Y including a fixed part, and a ring mechanism comprising'a movable member, a governor, interengaging elements on the governor and onthe movableV member ofthe firing mechanism, said interengaging elements cooperat` g ing to connect'the governor and the movable member ofthe firing mechanism, whereby the governor will retard the operation of the firing mechanism, a .carrier for l the governor, 'and means for holding the carrier on the liXed partof the gun, the last specified means beingireleasable to bring about va separation f of the'lnterengaging elements. I

5. In a device lof the class described, a gun i having a? firing holt, a rack mounted directly onthe iiringvbolt, a gear supported for rotation in the path ofthe rackon the firing bolt whereby the rackvwi-ll mesh with the gear for a predeterminedinterval, anda fly ball govex`V- nor connected to the gearand constituting means for exerting anv uninterrupted retarding action on the gear and on the .bolt during said interval.v n

5 In testimony' Whereof'I afliX my signature.

CHARLES c. MERTZ. 

